It's one of several DNA-driven activities detailed in a 2005 presentation that was just unearthed by Secrecy News. (That's a screen grab from the report, "Department of DefenseDNA Registry," to the right.)

At the time, 7,000 detainee samples had been fed into the Joint Federal Agencies Antiterrorism DNA Database – a combination effort from the Defense Department, the FBI, and the U.S. intelligence community. 10,000more were "inbound" from Iraq and Afghanistan.

An additional 6,000 samples were taken by the Armed Forces Medical Examiner's office. And an unspecified number were processed by the Armed Forces DNA Indentification Laboratory, which "provid[es] services... in support of personnel accounting, defense, law enforcement, humanitarian, national security and intelligence missions."

But most of the samples in the military DNA bank, at least in 2005, were from American troops. Back then, the Armed Forces Repository of Specimen Samples for the Identification of Remains contained data from 4,500,000servicemembers.